From fbdc4bbdf2bd0856f9620276f4112acacb4e4132 Mon Sep 17 00:00:00 2001
From: Emil Lerch <emil@lerch.org>
Date: Tue, 1 Apr 2025 13:45:34 -0700
Subject: [PATCH] skip old events on first run

---
 build.zig     |  2 ++
 build.zig.zon |  4 ++++
 src/root.zig  | 34 +++++++++++++++++++++++++++++-----
 3 files changed, 35 insertions(+), 5 deletions(-)

diff --git a/build.zig b/build.zig
index 1471aa6..a2f85b1 100644
--- a/build.zig
+++ b/build.zig
@@ -16,6 +16,7 @@ pub fn build(b: *std.Build) void {
     const optimize = b.standardOptimizeOption(.{});
 
     const mvzr_dep = b.dependency("mvzr", .{});
+    const zeit_dep = b.dependency("zeit", .{});
     // This creates a "module", which represents a collection of source files alongside
     // some compilation options, such as optimization mode and linked system libraries.
     // Every executable or library we compile will be based on one or more modules.
@@ -30,6 +31,7 @@ pub fn build(b: *std.Build) void {
     });
 
     lib_mod.addImport("mvzr", mvzr_dep.module("mvzr"));
+    lib_mod.addImport("zeit", zeit_dep.module("zeit"));
 
     // We will also create a module for our other entry point, 'main.zig'.
     const exe_mod = b.createModule(.{
diff --git a/build.zig.zon b/build.zig.zon
index 53d367d..3d9ffdf 100644
--- a/build.zig.zon
+++ b/build.zig.zon
@@ -40,6 +40,10 @@
             .url = "https://github.com/mnemnion/mvzr/archive/f8bc95fe2488e2503a16b7e9baf5e679778c8707.tar.gz",
             .hash = "mvzr-0.3.2-ZSOky95lAQA00lXTN_g8JWoBuh8pw-jyzmCWAqlu1h8L",
         },
+        .zeit = .{
+            .url = "https://github.com/rockorager/zeit/archive/44bebf856693332b168d8ba2c45b9d1ec15511de.tar.gz",
+            .hash = "zeit-0.0.0-5I6bk_pZAgB03N1p1GmVOZ--gOFwwQSRKj1UXb5tnaKS",
+        },
     },
     .paths = .{
         "build.zig",
diff --git a/src/root.zig b/src/root.zig
index 5df936e..8ec402d 100644
--- a/src/root.zig
+++ b/src/root.zig
@@ -1,5 +1,6 @@
 const std = @import("std");
 const mvzr = @import("mvzr");
+const zeit = @import("zeit");
 
 pub const Config = struct {
     syncthing_url: []const u8 = "http://localhost:8384",
@@ -43,7 +44,7 @@ pub const SyncthingEvent = struct {
         const data = value.object.get("data").?.object;
         return SyncthingEvent{
             .id = value.object.get("id").?.integer,
-            .time = value.object.get("time").?.string,
+            .time = try allocator.dupe(u8, value.object.get("time").?.string),
             .data_type = try allocator.dupe(u8, data.get("type").?.string),
             .folder = try allocator.dupe(u8, data.get("folder").?.string),
             .path = try allocator.dupe(u8, data.get("item").?.string),
@@ -84,6 +85,7 @@ pub const EventPoller = struct {
         const auth = try std.fmt.bufPrint(&auth_buf, "Bearer {s}", .{self.api_key});
 
         var retry_count: usize = 0;
+        const first_run = self.last_id == null;
         while (retry_count < self.config.max_retries) : (retry_count += 1) {
             var url_buf: [1024]u8 = undefined;
             var since_buf: [100]u8 = undefined;
@@ -126,17 +128,29 @@ pub const EventPoller = struct {
             var events = std.ArrayList(SyncthingEvent).init(self.allocator);
             errdefer events.deinit();
 
-            std.log.debug("Got event response:\n{s}", .{al.items});
             const parsed = try std.json.parseFromSliceLeaky(std.json.Value, aa, al.items, .{});
 
             const array = parsed.array;
+            if (first_run)
+                std.log.info("Got first run event response with {d} items", .{array.items.len})
+            else if (array.items.len > 0)
+                std.log.debug("Got event response:\n{s}", .{al.items});
+
+            var skipped_events: usize = 0;
             for (array.items) |item| {
-                const event = try SyncthingEvent.fromJson(self.allocator, item);
-                try events.append(event);
-                if (self.last_id == null or event.id > self.last_id.?) {
+                var event = try SyncthingEvent.fromJson(self.allocator, item);
+                if (self.last_id == null or event.id > self.last_id.?)
                     self.last_id = event.id;
+                if (first_run and try eventIsOld(event)) {
+                    skipped_events += 1;
+                    event.deinit(self.allocator);
+                    continue;
                 }
+
+                try events.append(event);
             }
+            if (skipped_events > 0)
+                std.log.info("Skipped {d} old events", .{skipped_events});
 
             return try events.toOwnedSlice();
         }
@@ -144,6 +158,13 @@ pub const EventPoller = struct {
     }
 };
 
+pub fn eventIsOld(event: SyncthingEvent) !bool {
+    const event_instant = try zeit.instant(.{ .source = .{ .rfc3339 = event.time } });
+    var recent = try zeit.instant(.{});
+    recent.timestamp -= std.time.ns_per_s * 60; // Grab any events newer than the last minute
+    return event_instant.time().before(recent.time());
+}
+
 pub fn executeCommand(allocator: std.mem.Allocator, command: []const u8, event: SyncthingEvent) !void {
     const expanded_cmd = try expandCommandVariables(allocator, command, event);
     defer allocator.free(expanded_cmd);
@@ -221,6 +242,7 @@ test "event parsing" {
     const event_json =
         \\{
         \\  "id": 123,
+        \\  "time": "2025-04-01T11:43:51.581184474-07:00",
         \\  "type": "ItemFinished",
         \\  "data": {
         \\    "folder": "default",
@@ -248,6 +270,7 @@ test "command variable expansion" {
         .data_type = "file",
         .folder = "photos",
         .path = "vacation.jpg",
+        .time = "2025-04-01T11:43:51.586762264-07:00",
     };
 
     const command = "convert ${path} -resize 800x600 thumb_${folder}_${id}.jpg";
@@ -298,6 +321,7 @@ test "end to end config / event" {
         \\{
         \\  "id": 123,
         \\  "type": "ItemFinished",
+        \\  "time": "2025-04-01T11:43:51.581184474-07:00",
         \\  "data": {
         \\    "folder": "default",
         \\    "item": "blah/test.txt",